This invention relates generally to a shielded electric connector a shielded electric cable assembly and a method of making a shielded electric cable assembly.
A shielded electric cable assembly generally comprises a shielded electric cable, that has a conductor core that is surrounded by an inner insulation jacket, an intermediate conductive layer, and an outer insulation jacket. An inner terminal is attached to the conductor core as part of the assembly for making an electric connection to a mating terminal and a shield terminal is attached to the conductive layer. The conductive layer and shield terminal shield any electronic devices in the vicinity of the shielded electric cable assembly from electromagnetic interference (generally designated EMI) caused by electric current flowing through the conductive core and inner terminal.
A common shielded electric cable has an intermediate conductive layer in the form of a metallic braid that is woven around the inner insulation jacket. Terminals that include core crimp wings for attaching a terminal to the conductor core of an electric cable by a crimping operation are well known. Likewise terminals that include both core and insulation crimp wings for attaching a terminal to both the core and insulation jacket of an electric cable are also well known.
U.S. Pat. No. 6,257,931 B1 issued to Kazuaki Sakurai et al. Jul. 10, 2001, discloses a shielded electric cable assembly in FIG. 1. The shielded electric cable assembly comprises a shielded electric cable and an inner terminal that is attached to an exposed end portion of a conductor core of the shielded electric cable by core crimp wings to form an inner member sub-assembly as shown in FIG. 3 of the Sakurai et al. patent. The shielded electric cable assembly also includes an outer terminal sub-assembly comprising an inner insulating housing inside an outer or shielding terminal as shown in FIG. 4. The inner sub-assembly is connected to the outer sub-assembly by inserting inner terminal into the inner insulating housing of the outer terminal sub-assembly as shown in FIG. 1. The shielding terminal is then attached to the shielded electric cable by two sets of crimp wings that are crimped around the exposed end of the conductive layer and the outer insulation jacket of the shielded electric cable as shown in FIG. 8. The shielding terminal includes an integral lid member that is pressed against the conductive layer of the shielded electric cable to close an opening at the rear of the shielding terminal after the inner terminal is inserted into the inner insulating housing.
The shielded electric cable assembly disclosed in the Sakurai et al. patent is expensive and difficult to manufacture primarily because it involves the fabrication of two separate sub-assemblies that must be attached to the electric cable at different times, namely an inner terminal sub-assembly that is attached to the cable and an outer or shielding terminal sub-assembly which must be joined to the inner sub-assembly and then attached to the cable.
U.S. Pat. No. 7,160,150 B2 issued to Sebastien Annequin Jan. 9, 2007 discloses a shielded electric cable assembly that does not require an initial subassembly attached to the shielded electric cable. The shielded electric cable assembly disclosed in the Annequin patent has an electric connector that is attached to a shielded electric cable assembly in a single operation or series of operations. The electric connector comprises an outer body, an insulating body and a central contact (inner terminal). Central contact has a forward portion is disposed inside the insulating body and a protruding rearward portion equipped with core crimp wings that are supported on an integral extending bearing portion of the insulating body. After the shielded electric cable is prepared as shown in FIG. 2 of the Annequin patent, the electric connector is attached to the bared end of the core of the shielded electric cable in a crimping operation as shown in FIGS. 6, 7 and 8 of the Annequin patent. The electric connector is also attached to the bared end of the conductive layer and the end of the insulation jacket of the shielded electric cable by braid crimp wings and insulation crimp wings respectively; the braid crimp wings and insulation crimp wings being part of the shielding terminal. The Annequin patent does not specify when the braid and insulation crimp wings are crimped.
While the U.S. Pat. No. 7,160,150 B2 does disclose a shielded electric cable assembly that can be fabricated in an easier manner, the Annequin shielded cable assembly nevertheless has a draw back in that the shielded electric cable assembly has a large opening in the shielding terminal that exposes the core crimp wings of the inner terminal thus compromising the shielding efficiency of the arrangement.